The present invention relates to a method for operating an RLAN arrangement, said RLAN arrangement comprising a plurality of communication units or communication nodes.
Nowadays, wireless communication with the networks becomes more and more popular. Therefore, in the field of wireless local area networks or WLANs, so-called radio local area networks or RLANs, were introduced. Such an RLAN comprising a plurality of communication units or communication nodes, one of which being a central controller CC or an access point AP and the latter of which being so-called wireless terminals WT.
As the communication of an RLAN is established by transmitting and receiving radiation in the radio frequency range interference may occur with other and separated RLAN arrangements and/or with external radar services or radar sources.
In particular, in the 5 GHz band or range communication was until now restricted to radar services and radar devices. Nowadays, said former radar services are referred to as primary users for the 5 GHz band or range, whereas RLAN arrangements or concepts in the 5 GHz band or range are referred to as secondary users. That means, that the complete 5 GHz band or range has to be shared by said primary users or radar services and by said secondary users or RLAN arrangements giving a communication priority to the primary users. In particular the ranges from 5,150 GHz to 5,350 GHz and from 5,470 GHz to 5,725 GHz are allocated to RLANs.
For establishing and ruling such a sharing concept, regulatory requirements for the secondary users have been established. That means that the presence of primary users has to be checked during the operation of the secondary users. If a primary user occurs and a coincidation overlap of the communication channels has to be expected, the communication channel has to be changed by the secondary users.
Known methods for monitoring the presence of primary users or radar services are not reliable enough and decrease the communication efficiency during known RLAN arrangements.